Synopsis
Matsuko Arita is a background presence in Class 3-3 for much of the story, sociable with a wide circle of classmates including Yumi Ogura and Sachiko Nakajima. Friendly on the surface, she is also among the students swept up in the accusations against Mei Misaki later in the story.
During the class trip she rooms with Sayuri Kakinuma, and the two are together when chaos breaks out at the inn overnight. Separated in the confusion that follows, Matsuko is caught in an explosion and thrown through a window, surviving with only minor injuries.
She goes on to help several other survivors, including a badly hurt Naoya Teshigawara, once she reaches safety outside, making her one of the class's few outright survivors of that night.
